Smarter way of handling settings

Removed monkeypatching from cms.__init__
Removed cms.conf.*
Added cms.utils.conf.get_setting(name)
Refactored all (CMS) setting accesses throughout the code base

This should fix issues with more recent gunicorn version (>0.12) as
well as make the code less hacky.

Known issues on this branch:

* ApphooksPageLanguageUrlTestCase.test_page_language_url_for_apphook
  currently fails, not sure why.
* SettingsTests.test_cms_templates_length,
  SettingsTests.test_cms_templates_none and
  SettingsTests.test_cms_templates_valid all fail currently because
  cms.conf.patch.post_patch and cms.conf.patch.post_patch_check are
  no longer available.
Merge branch 'develop' into dont-patch-configs

Conflicts:
	cms/admin/change_list.py
	cms/admin/pageadmin.py
	cms/api.py
	cms/models/pagemodel.py
	cms/signals.py
	cms/tests/admin.py
	cms/tests/page.py
don't test non-existing patching magic anymore
fixed typo in merge
Fixed cms.utils.i18n.get_languages failing due to missing default

Also ensure that get_settings('LANGUAGES') has a useful 'default' key
Added tests for CMS_LANGUAGES without a 'default' key
Merge remote-tracking branch 'origin/develop' into dont-patch-configs

Conflicts:
	cms/__init__.py
fixed legacy warning
Installation checking infrastructure

* Added cms.utils.check.check
* Added 'cms check' command
* Added infrastructure to write installation checks
* Added first simple sekizai check
fixed runshell.py
fixed reporting of cms.utils.check.FileSectionWrappers
fixed old-style language setting transition
Added more checks to 'cms check'

* Added checks for deprecated settings CMS_MODERATOR and CMS_FLAT_URLS
* Added check for new-style language setting
* Added more checks for sekizai
Finished cms check command

* Added docstrings to cms.utils.check module
* Added tests for cms.utils.check
* Fixed sekizai check function always reporting successful
added docs for cms check and get_settings
Added support for ancient Python versions (aka 2.5)
Added cms check to tutorial
renamed cms.utils.conf.get_setting to get_cms_setting
added cms check documentation
Merge pull request #1565 from ojii/dont-patch-configs

Smarter way of handling settings (fixes gunicorn/flup)